The 11.7T/5 cm superconducting magnet, which has been in service in this laboratory since August 1979, is now outdated and has seriously hampered, or made it impossible, for our users to perform modern 2D-NMR experiments at 500 MHz. The objective of this proposal is to sharply upgrade the performance of our 500 MHz NMR spectrometer by replacing our obsolete magnet with a new one having superior overall performance and capabilities. Instrumentation funds are sought to purchase a state-of-the-art, high homogeneity 11.7T, wide bore (8.9 cm) superconducting magnet system (Oxford Instruments, Inc.) equipped with room temperature shims and shim power supply, spinner tube and spin rate meter, and liquid cryogen level meters. The superior homogeneity of the new magnet will make possible 2D-NMR studies of proteins and nucleic acids in water solvent so that sequential assignment strategies can be implemented. The high field and large bore are absolutely essential for studies of metabolic pathways in vivo spectroscopy and imaging of cannibinoid analogs in rat brain. The requested instrument is the highest field magnet with a clear room temperature bore of 8.9 cm. If an award is made, this magnet would be the first of its kind in this country.